module decoder24 (
    input                [1:0]       data_in     ,
    output      reg      [3:0]       q
);

always @(*) begin
    case (data_in)
        2'b00: q <= 4'b1110;
        2'b01: q <= 4'b1101;
        2'b10: q <= 4'b1011;
        2'b11: q <= 4'b0111;
        default: q <= 4'bZZZZ;
    endcase
end
endmodule //decoder24